Time of Flight sensors have become increasing popular in many applications from the car to the mobile phone. The Covid-19 pandemic has been driving the need for contactless interfaces, and ToF sensors have been a key part of this.
However Maxim Integrated is taking on ToF sensors with an array of infrared sensors that can detect hand gestures for a fraction of the cost. This is initially aimed at car designs to avoid having to touch the controls, for a tenth the price. That cost reduction opens up new consumer and industrial touch-free interface designs that avoid cross-contamination.
ToF sensors tend to use CMOS image sensors as the receivers for sensing, which can make them expensive. Other approaches have been using neural networks and time information to simplify these receivers.
Instead, Maxim uses an array of 60 photo diodes, LED driver and internal LDO in a 4x4mm chip for design that is 75 percent smaller than a ToF sensor and can be paired with a small microcontroller, rather than the larger microprocessors that more complex solutions require.
This identifies nine gestures, including swipe, rotations, air link and 3x2 proximity zones with low lag time in a single chip rather than three. This cost and size reduction opens up gesture-sensing not just in automotive but in consumer and industrial applications such as smart home hubs, thermostats and others, all without touching the device.
“Although ToF-based systems enabled gesture-sensing in luxury models, automakers are hopeful to add this stylish and life-saving feature to higher volume product tiers as well,” said Sachin Garg, associate vice president at market researcher MarketsandMarkets. “What designers need is a lower cost alternative to today’s systems in order to make the economics of gesture-sensing controls more feasible for non-luxury models.”
Next: evaluation kit under NDA